Port yuzu-emu/yuzu#2511: "common/file_util: Minor cleanup" (#4782)

* common/file_util: Make IOFile's WriteString take a std::string_view

We don't need to force the usage of a std::string here, and can instead
use a std::string_view, which allows writing out other forms of strings
(e.g. C-style strings) without any unnecessary heap allocations.

* common/file_util: Remove unnecessary c_str() calls

The file stream open functions have supported std::string overloads
since C++11, so we don't need to use c_str() here. Same behavior, less
code.

* common/file_util: Make ReadFileToString and WriteStringToFile consistent

Makes the parameter ordering consistent, and also makes the filename
parameter a std::string. A std::string would be constructed anyways with
the previous code, as IOFile's only constructor with a filepath is one
taking a std::string.

We can also make WriteStringToFile's string parameter utilize a
std::string_view for the string, making use of our previous changes to
IOFile.

* common/file_util: Remove duplicated documentation comments

These are already present within the header, so they don't need to be
repeated in the cpp file.

* common/file_util: Make GetCurrentDir() return a std::optional

nullptr was being returned in the error case, which, at a glance may
seem perfectly OK... until you realize that std::string has the
invariant that it may not be constructed from a null pointer. This
means that if this error case was ever hit, then the application would
most likely crash from a thrown exception in std::string's constructor.

Instead, we can change the function to return an optional value,
indicating if a failure occurred.

* common/file_util: Remove unnecessary return at end of void StripTailDirSlashes()

While we're at it, also invert the conditional into a guard clause.
This commit is contained in:
Tobias 2019-06-08 00:23:57 +02:00 committed by GitHub
parent 49f6f11462
commit ef73de9386
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 24 additions and 45 deletions

View file

@ -29,12 +29,12 @@ Config::Config() {
Config::~Config() = default;
bool Config::LoadINI(const std::string& default_contents, bool retry) {
const char* location = this->sdl2_config_loc.c_str();
const std::string& location = this->sdl2_config_loc;
if (sdl2_config->ParseError() < 0) {
if (retry) {
LOG_WARNING(Config, "Failed to load {}. Creating file from defaults...", location);
FileUtil::CreateFullPath(location);
FileUtil::WriteStringToFile(true, default_contents, location);
FileUtil::WriteStringToFile(true, location, default_contents);
sdl2_config = std::make_unique<INIReader>(location); // Reopen file
return LoadINI(default_contents, false);

View file

@ -77,16 +77,17 @@ namespace FileUtil {
// Remove any ending forward slashes from directory paths
// Modifies argument.
static void StripTailDirSlashes(std::string& fname) {
if (fname.length() > 1) {
std::size_t i = fname.length();
while (i > 0 && fname[i - 1] == DIR_SEP_CHR)
--i;
fname.resize(i);
}
if (fname.length() <= 1) {
return;
}
// Returns true if file filename exists
std::size_t i = fname.length();
while (i > 0 && fname[i - 1] == DIR_SEP_CHR) {
--i;
}
fname.resize(i);
}
bool Exists(const std::string& filename) {
struct stat file_info;
@ -106,7 +107,6 @@ bool Exists(const std::string& filename) {
return (result == 0);
}
// Returns true if filename is a directory
bool IsDirectory(const std::string& filename) {
struct stat file_info;
@ -131,8 +131,6 @@ bool IsDirectory(const std::string& filename) {
return S_ISDIR(file_info.st_mode);
}
// Deletes a given filename, return true on success
// Doesn't supports deleting a directory
bool Delete(const std::string& filename) {
LOG_TRACE(Common_Filesystem, "file {}", filename);
@ -164,7 +162,6 @@ bool Delete(const std::string& filename) {
return true;
}
// Returns true if successful, or path already exists.
bool CreateDir(const std::string& path) {
LOG_TRACE(Common_Filesystem, "directory {}", path);
#ifdef _WIN32
@ -193,7 +190,6 @@ bool CreateDir(const std::string& path) {
#endif
}
// Creates the full path of fullPath returns true on success
bool CreateFullPath(const std::string& fullPath) {
int panicCounter = 100;
LOG_TRACE(Common_Filesystem, "path {}", fullPath);
@ -229,7 +225,6 @@ bool CreateFullPath(const std::string& fullPath) {
}
}
// Deletes a directory filename, returns true on success
bool DeleteDir(const std::string& filename) {
LOG_TRACE(Common_Filesystem, "directory {}", filename);
@ -251,7 +246,6 @@ bool DeleteDir(const std::string& filename) {
return false;
}
// renames file srcFilename to destFilename, returns true on success
bool Rename(const std::string& srcFilename, const std::string& destFilename) {
LOG_TRACE(Common_Filesystem, "{} --> {}", srcFilename, destFilename);
#ifdef _WIN32
@ -267,7 +261,6 @@ bool Rename(const std::string& srcFilename, const std::string& destFilename) {
return false;
}
// copies file srcFilename to destFilename, returns true on success
bool Copy(const std::string& srcFilename, const std::string& destFilename) {
LOG_TRACE(Common_Filesystem, "{} --> {}", srcFilename, destFilename);
#ifdef _WIN32
@ -323,7 +316,6 @@ bool Copy(const std::string& srcFilename, const std::string& destFilename) {
#endif
}
// Returns the size of filename (64bit)
u64 GetSize(const std::string& filename) {
if (!Exists(filename)) {
LOG_ERROR(Common_Filesystem, "failed {}: No such file", filename);
@ -350,7 +342,6 @@ u64 GetSize(const std::string& filename) {
return 0;
}
// Overloaded GetSize, accepts file descriptor
u64 GetSize(const int fd) {
struct stat buf;
if (fstat(fd, &buf) != 0) {
@ -360,7 +351,6 @@ u64 GetSize(const int fd) {
return buf.st_size;
}
// Overloaded GetSize, accepts FILE*
u64 GetSize(FILE* f) {
// can't use off_t here because it can be 32-bit
u64 pos = ftello(f);
@ -376,7 +366,6 @@ u64 GetSize(FILE* f) {
return size;
}
// creates an empty file filename, returns true on success
bool CreateEmptyFile(const std::string& filename) {
LOG_TRACE(Common_Filesystem, "{}", filename);
@ -501,7 +490,6 @@ bool DeleteDirRecursively(const std::string& directory, unsigned int recursion)
return true;
}
// Create directory and copy contents (does not overwrite existing files)
void CopyDir(const std::string& source_path, const std::string& dest_path) {
#ifndef _WIN32
if (source_path == dest_path)
@ -538,8 +526,7 @@ void CopyDir(const std::string& source_path, const std::string& dest_path) {
#endif
}
// Returns the current directory
std::string GetCurrentDir() {
std::optional<std::string> GetCurrentDir() {
// Get the current working directory (getcwd uses malloc)
#ifdef _WIN32
wchar_t* dir;
@ -550,7 +537,7 @@ std::string GetCurrentDir() {
#endif
{
LOG_ERROR(Common_Filesystem, "GetCurrentDirectory failed: {}", GetLastErrorMsg());
return nullptr;
return {};
}
#ifdef _WIN32
std::string strDir = Common::UTF16ToUTF8(dir);
@ -561,7 +548,6 @@ std::string GetCurrentDir() {
return strDir;
}
// Sets the current directory to the given directory
bool SetCurrentDir(const std::string& directory) {
#ifdef _WIN32
return _wchdir(Common::UTF8ToUTF16W(directory).c_str()) == 0;
@ -723,8 +709,6 @@ void SetUserPath(const std::string& path) {
g_paths.emplace(UserPath::DLLDir, user_path + DLL_DIR DIR_SEP);
}
// Returns a string with a Citra data dir or file in the user's home
// directory. To be used in "multi-user" mode (that is, installed).
const std::string& GetUserPath(UserPath path) {
// Set up all paths and files on the first run
if (g_paths.empty())
@ -732,11 +716,11 @@ const std::string& GetUserPath(UserPath path) {
return g_paths[path];
}
size_t WriteStringToFile(bool text_file, const std::string& str, const char* filename) {
return FileUtil::IOFile(filename, text_file ? "w" : "wb").WriteBytes(str.data(), str.size());
std::size_t WriteStringToFile(bool text_file, const std::string& filename, std::string_view str) {
return IOFile(filename, text_file ? "w" : "wb").WriteString(str);
}
size_t ReadFileToString(bool text_file, const char* filename, std::string& str) {
std::size_t ReadFileToString(bool text_file, const std::string& filename, std::string& str) {
IOFile file(filename, text_file ? "r" : "rb");
if (!file)
@ -746,13 +730,6 @@ size_t ReadFileToString(bool text_file, const char* filename, std::string& str)
return file.ReadArray(&str[0], str.size());
}
/**
* Splits the filename into 8.3 format
* Loosely implemented following https://en.wikipedia.org/wiki/8.3_filename
* @param filename The normal filename to use
* @param short_name A 9-char array in which the short name will be written
* @param extension A 4-char array in which the extension will be written
*/
void SplitFilename83(const std::string& filename, std::array<char, 9>& short_name,
std::array<char, 4>& extension) {
const std::string forbidden_characters = ".\"/\\[]:;=, ";

View file

@ -9,6 +9,7 @@
#include <fstream>
#include <functional>
#include <limits>
#include <optional>
#include <string>
#include <type_traits>
#include <vector>
@ -115,7 +116,7 @@ u64 ScanDirectoryTree(const std::string& directory, FSTEntry& parent_entry,
bool DeleteDirRecursively(const std::string& directory, unsigned int recursion = 256);
// Returns the current directory
std::string GetCurrentDir();
std::optional<std::string> GetCurrentDir();
// Create directory and copy contents (does not overwrite existing files)
void CopyDir(const std::string& source_path, const std::string& dest_path);
@ -141,8 +142,9 @@ const std::string& GetExeDirectory();
std::string AppDataRoamingDirectory();
#endif
size_t WriteStringToFile(bool text_file, const std::string& str, const char* filename);
size_t ReadFileToString(bool text_file, const char* filename, std::string& str);
std::size_t WriteStringToFile(bool text_file, const std::string& filename, std::string_view str);
std::size_t ReadFileToString(bool text_file, const std::string& filename, std::string& str);
/**
* Splits the filename into 8.3 format
@ -228,8 +230,8 @@ public:
return WriteArray(&object, 1);
}
std::size_t WriteString(const std::string& str) {
return WriteArray(str.c_str(), str.length());
std::size_t WriteString(std::string_view str) {
return WriteArray(str.data(), str.length());
}
bool IsOpen() const {
@ -267,8 +269,8 @@ private:
template <typename T>
void OpenFStream(T& fstream, const std::string& filename, std::ios_base::openmode openmode) {
#ifdef _MSC_VER
fstream.open(Common::UTF8ToUTF16W(filename).c_str(), openmode);
fstream.open(Common::UTF8ToUTF16W(filename), openmode);
#else
fstream.open(filename.c_str(), openmode);
fstream.open(filename, openmode);
#endif
}